Floating draw-bridge



will not carry it o' the line.

UNITED STATES PATENT OFFICE.

NAP. B. PROOTOR, OF BURLINGTON, VERMONT.

FLOATING- DRAW-BRIDGE.

Specification of Letters Patent No. 14,928, dated May 20, 1856.

To all whom t may concern.'

Be it known that I, NAPOLEON B. PRoo- TOR, of Burlington, in the countyof Chittenden and State of Vermont, have invented a new and ImprovedMode of Constructing .l

Floating Draw-Bridges Across Navigable and other Streams or Vaters; andI do hereby declare that the following is a full and exact descriptionthereof, reference being had to the accompanying drawings and to theletters of reference marked thereon.

The nature of my invention consists in construct-ing a dock or wharf oneach side of and partly within the stream or other water to be crossedby a floating bridge, leaving sufficient space open between such docks,or wharves, for the passage of vessels, within one of which docks orwharves a slip is constructed and a suit-able boat placed therein, whichboat can be worked forward speedily, by steam or other power, to theopposite dock or wharf. 4and thus form a connection therewith, and whenthus connected the boat becomes a bridge; and when it is worked backinto t-he slip, the space between the docks or wharves is left open andfree for the passage of vessels. Said slip and boat are made about twicethe length of the space leftl open for navigation so that only abouthalf the length of the boat is worked out of the slip in making theconnection, the other part of the boat remaining in the slip, and, byreason thereof the sides of the slip keep the boat in nearly a directline so that wind, tide or current The opposite dock or wharf may beconstructed with a recess, in the end thereof fronting the water, fort-he reception of the end. of the boat, or the end may be made straight,with timbers bolted thereon to serve as guides in conducting the end ofthe boat to its place, in making the connection.

To enable others skilled in the artl to make use of my invention, I willproceed to describe its construction and Operation when used as arailroad bridge.

I construct a dock or wharf upon each side of, or wholly or partly in astream, bay or other water, necessary to be crossed with a railroadtrack, leaving between said docks or wharves an open space for thepassage of vessels. In one of these docks or wharves I construct a slip,sufHciently large to receive a boat, of proper dimensions, in which slipI place such boat, (said slip and boat being about twice the lengt-h ofthe open space between such dock or wharves,) and the boat is workedforward to and against the opposite dock or wharf, and thus makes aconnected and continuous line, as shown in the accompanying drawings,numbered 3 and 4. Sections Nos. 1 and 3, in said drawings, Nos. 3 and 4,represent portions of the road bed and track. Timbers, marked a, in saiddrawings, are laid upon said road bed, and upon said timbers portions ofthe track is laid upon longitudinal timbers, resting thereon.

I construct a platform, in two parts, which is placed upon the dock orwharf containing the slip and over and above the slip and boat withinit, one part of which platform is connected with the permanent railroad,and is constructed as follows: A permanent cross timber is placed underlongitudinal timbers where the permanent road ends and t-he bridgecommences, as shown at points marked c, in sections 1 and 3, of drawingsNos. 3 and 4. Permanent frames are also constructed upon each side ofsaid dock or wharf, as shown by posts and beam, marked in said drawingNo. 3. Timbers are laid across said dock or wharf as shown by timbersrepresented in said drawing' Nos. 3 and 4, marked (l, which are attachedto said frames by having bolts pass through them, near each end of saidtimbers, and through the beam, which is part of said frame, as shown atpoints, marked e, in drawing No. 3, which bolts are held with screw nutsas shown at points marked f, in said drawing No. 3, by means of whichscrew nuts said timbers, which in part, support said platform, areraised, or lowered, as may be necessary to adapt the machine to high orlow water. Upon these timbers, as shown in said drawing No. 4, marked c,d, cl, four longitudinal timbers are laid which are connected with thepermanent road, by hinges, at points marked g, in drawing No. 4. Theother part of said platform is constructed of four longitudinal timbers,resting upon cross timbers, all marked 7L, in drawing No. 4, and boltedtogether and braced, as shown at points marked i, in drawing No. 3,which latter part of said platform is connected wit-h the former, byhinges, at points marked y', in drawing No. 4, the other end of saidplatform resting upon the deck of said boat. In the outer longitudinaltimbers of said platform, at

points marked k, in drawing No. 4, iron wheels are inserted, which runupon the deck of said boat, and when the boat is worked forward to theopposite dock, said wheels fall in to sockets in the deck of said boat,and thereby drop that end of the platform which rests upon the boat, andconnect the two longitudinal timbers of said platform with timbersmarked Z, in drawing No. 4, which are attached permanently to the deckof said boat, and upon which a section of railroad track is laid.

I attach a chain to the boat, upon its deck, near each end of the boatas shown at points marked fm, in drawing No. 4, which runs around acapstan, placed .upon the side of the dock or wharf in which the slip isconstructed, as shown at point marked n, in drawing No. 4, and byworking this capstan with steam, or other power, the boat is movedforward to form a connected line of road or back into the slip, leavingthe draw open. Underneath the part of the platform which so rests inpart upon the deck of said boat, I place a lever, attached to the deck,as shown at point marked 0, in drawing No. 4, with which that part ofsaid platform is raised, so that the timbers laid upon and attached tothe deck of the boat (and upon which track is laid) pass under theplatform as the boat is moved into the slip.

Upon the opposite dock or wharf I construct a platform substantiallylike that part of the platform last above described, viz, with fourlongitudinal timbers, as shown in said drawing No. 4, which timbers, asrepresented in said drawing, are severally marked y, with cross timbersunderneath, also marked 7?, in said drawing, which longitudinal timbersare connected with the permanent railroad by hinges, as shown in saiddrawing No. 4, at points marked g. Said platform is held together bybraces and bolts, as shown in drawing No. 3, at points marked r. Theother end of said platform (next to the water or open space) is raisedand lowered by chains attached thereto, which pass over pulleys in aframe above it, which frame I construct as follows: A post on each sideand near that end of said platform last described, is set and madepermanent in said dock or wharf, with a cross beam on the top of saidposts, as shown in drawing No. 2, marked s, which chains are attachedto, and worked by a winch, on the side of one of the posts, as shown indrawings No. 2 and 3, at points marked t, (by means of which the saidplatform is raised and lowered,) and when the connection is formed byworking the boat forward from the slip to the opposite dock or wharf,the end of said last mentioned platform (thus raised and lowered) rests`upon said boat, forming a continuous line of road or track upon whichlocomotives and cars pass and repass over and upon said boat andplatforms, and while the is passing the platforms sink with the boat,and they rise with it when the train passes off, keeping the connectionunbroken, the platforms thus becoming self adjusting. The rail roadtrack upon said platforms is made by laying the rails upon the two innerlongitudinal timbers of said platforms.

What I claim as my invention and desire to secure by Letters Patent isThe construction of a floating draw bridge, by erect-ing a wharf or dockon each side of, or partly or wholly within, rivers, or other waters,over or across which such bridge may be required, with a slip in one ofsaid docks or wharves of a suitable size for the reception of a boat ofproper dimensions, viz., nearly as wide as the slip and about twice thelength of theropen space between the docks or wharves (through whichopen space vessels may pass and repass) which boat, by steam, or otherpower, can be readily worked forward from the slip to the opposite dockor wharf and thus form a connection therewith, and back again into theslip, leaving the space, or channel open for the passage and re-passageof vessels, substantially in the manner and for the purposes abovedescribed.

NAPOLEON B. VPROCTOR. Witnesses:

WM, WESTON, WM. G. SHAW.

